Modern audio communication systems, such as microphone systems, provide a reliable infrastructure to transmit voice signals. A wireless microphone system generally comprises an acoustic source such as a microphone and a receiver that are linked to each other via a transmitter. The transmitter therefore facilitates a wireless link between the acoustic energy from the audio source and the receiver.
These audio components, i.e. the microphone, transmitter and receiver, are commonly available in the audio industry. The microphone is an audio transducer in which acoustic energy from a sound source is converted into electric output through an oscillating element that oscillates in response to the transmitted acoustic energy. The electric output is fed to the transmitter.
The transmitter is wireless, and is available either as a handheld device or as a body pack. The transmitter sends the microphone's electric output to the receiver via a signal transmission captured by the receiver's antenna. The signal transmission may be, for example, a Radio Frequency (RF) signal, and a pilot tone is provided to so that the receiver can recognize the signal that is being sent from the transmitter that carries the microphone output.
The receivers can be either a diversity or a non-diversity system. Diversity wireless receiver systems are highly desirable because they effectively combat the most common problem with wireless microphone equipment, namely signal dropouts due to multi-path. Diversity wireless systems also almost always have better operating range than similar non-diversity systems.
Wireless receivers must have either one or two external antennas, and there should be a clear open-air path between these antennas and the transmitter's antenna. Every wireless microphone system operates on a specific frequency. The government dictates which frequency ranges can be used by wireless systems. By government policy, all frequencies are shared by a large number of users across the country. There must be one transmitter and one receiver to make a complete wireless system, and they both must be on the same frequency.
The performance of such wireless microphone systems typically is tested and evaluated at the physical location of their audio components, or at a distant testing and repairing facility. However, both of these situations introduce their respective disadvantages in that they require either a shipment of the wireless microphone components to the distant facility, or require an arrangement for the physical presence of a qualified technical individual at the location where the wireless microphone system is being used.
Recommended Standard (RS) 232 is a commonly utilized standard for serial communications in information handling systems. RS-232 has been around as a standard for decades as an electrical interface between Data Terminal Equipment (DTE) and Data Circuit-Terminating Equipment (DCE). Examples of DTEs include Personal Computers (PCs), workstations, file servers, or print servers that, as a group, are all often referred to as end stations. Examples of DCEs include intermediate network devices that receive and forward data frames across a network that are either (i) standalone devices such as repeaters, network switches, and routers or (ii) communications interface units such as interface cards and modems. RS-232 is used for asynchronous data transfer as well as synchronous links.
The Ethernet has replaced serial ports to dominate the way computers communicate, and has become the communications method of choice. For example, Ethernet Local Area Networks (LANs) consist of network nodes and interconnecting media. The network nodes fall into two major classes: DTEs and DCEs. Typically micro-controller based projects communicate over 10base T Ethernet or higher, and Ethernet boards allow data traffic to and from the Internet. The Internet is only one type of a communication network. Other communication networks may be Local Area Networks (LAN), Wide Area Networks (WAN), Integrated Services Digital Networks (ISDN), wireless networks, and other similar networks to transfer data between two points.